Internal-combustion engine.



G. C. LONGARD.

. INTERNAL COMBUSTION ENGINE.

APPLICATION FILED 0.0T.26, 1912.

Patented June 23, .1914.

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CLARENCE C. LONGARD, 0F HALIFAX, NOVA SGOTIA, CANADA.

INTERNAL-GQMIBUSTION IENGINE.

Specification of 'LettersZPatent. Patented 111 11623, 19 14,

Application filedDotober 26, 1912. Serial No. 727,970.

To all whom it may concern Be it known that I, CLARENCE C. LON- earn, citizen of Canada, residing at Halifax, in the Province of Nova Scotia and Dominion of Canada, have invented new and useful Improvements in Internal-Combustion Engines, of which the following a specification.

This invention relates to an internal combustion engine which operates on the two cycle principle and embodies means whereby the spent gases are forced out of .the cylinder through the instrumentality of an auxiliary piston in the cylinder while the main piston uncovers the exhaust port.

The invention has for its general object to improve and simplify the construction and operation of internal combustion engines whereby the efficiency is greatly increased, .a minimum number of parts employed and mechanically actuated valves eliminated.

Another object of the invention is the employment of an auxiliary piston which is pneumatically or spring-actuated at the end of the power stroke of the main piston for forcing out or displacing the vspent" gases, and for simultaneously sucking inthe next charge of explosive mixture, while on the return stroke the auxiliary piston moves with the main piston whereby the previously drawn in charge is compressed andfinally transferred to the explosion chamber between the pistons, so that upon ignition the explosive forces of the gases will impart a power impulse to the main piston, there being a power impulse imparted for-each rotation of the crank shaft as in two cycle engines. I

With these objects in view, and others, as will appear as the description proceeds, the invention comprises the various novel features of construction and arrangement of parts as will be more fully set forth herein after and defined in the claim.

In the accompanying drawing which illustrates certain embodiments of the invention: Figure 1 is a central vertical section of an engine cylinder and accompanying parts for carrying out the invention. Fig. 2 is a fragmentary detail view of a modified form.

Similar reference characters are employed to designate corresponding parts in the figure.

Referring to the drawing: A designates a water jacketed or other cooled cylinder which is shown in the present instance of uniform bore, and containing the main piston 1 and the auxiliary piston 2 that are separated by an explosion or combustion chamber 3, which chamber has a fuel. ad- HHSS IOIIPOIt 4 at a p0int near the limit of the nstroke of the piston 1, and an exhaust port 5 located in the cylinder wall at the limit of the outstroke of the piston 1. The explosive charge in the chamber 3 a suitable ignition device (not shown) mounted in the cavity 6.

Between the head 7 of the cylinder and the is fired by auxiliary piston 2, is a combined charge suct1on and compression chamber 8 which is provided with a port 9 through which the charge is sucked in during the down or outstroke of the auxiliary piston, and throughwhich the charge is forced out during the up or instroke. The port 9 communicates ,with the valve chamber 10 which communicates with a carbureter or other mixing device through an openin or conduit 11 there being in the valve chamber 10 a puppet check valve 12 which opens toward the port 4 of the cylinder so that the charge can be transferred from the chamber 8 to the explosion chamber 3 through the port-9, valve casing 10 past the valve 12 and through the port 4. This valve 12 opens automatically underthe pressure of the compressed charge in the chamber 8 at the time the pressure in the chamber 3 is approximately at atmosphere by-the opening of the exhaust port 5.

Although the'auxiliary piston 2 is meit is prevented from coming into contact with thela-tter by means of a cushioning device which comprises a stem 13, centrally disposed on the auxiliary piston 2, and adapted to enter a depression or pocket 14 carried bythe head 15 of'the main piston. As the stem 13 enters the pocket or cylinder 14, the gas entrapped in the latter becomes compressed and serves as a cushion between the pistons, and furthermore the pistons are thus maintained a suitable distance apart, as on the up or instroke, so that a charge of gas or mixture can enter the space or chamber 3 at the proper time.

vice is also provided for the auxiliary piston to Withstand the shocks of the explosions exerted thereon, such device comprising a stem or plunger 16 which reciprocates in a tubular neck or extension 17 projecting outwardly from the cylinder head 7, and on the outer end of extension 7 is formed a cham- A cushioning dei chanically independent of the main piston,

' sion in the chamber 18. This compressed ber 18 entirely closed to the atmosphere. At the inner portion of the neck is a port 19 that is uncovered by the stem or plunger 16 when the auxiliary piston 2 is at the end of its down or instroke, and consequently air will fill the chamber 18 and neck 17 so as to be compressed during the reverse stroke of the auxiliary piston 2 and its stem 16, this compression of the air in the chamber 18 serving to effectually cushion the auxiliary piston. It will be noted that the port 9 is somewhat separated from the head 7,

so that when the port 9 is covered by the auxiliary piston some gas or mixture will be entrapped in the chamber 8 and subjected to compression, adding thereby a cushioning efiect.

In describing the cycle of operation, it

will be assumed that the piston 1 is at the end ofits power stroke with the exhaust port 5 open. During the power stroke the auxiliary piston 2 is at'the limit of its upward movement; with air under compres air acts on the plunger or stem 16 and quickly forcest-he auxiliary piston downwardly; when the exhaust port 5 is opened, thereby expelling theexhaust gases. The

. two pistons are prevented from coming in contact by the cushioning device 13, 14. During this downward stroke of the auxiliary piston 2 the next charge is sucked into the chamber 8 through the port 9. Conse quently on the in or return stroke of the main piston 1, the auxiliary piston 2moves with itand compresses the charge in the chamber 8, andv finally a point is reached when the valve 12 will open and" the coinpressed charge will be automatically transferred from the chamber 8 to the chamber 13. The igniting device then fires the charge which imparts a power stroke to the piston 1, while the auxiliary piston is cushioned by the compressed air in the chamber 18 and art, but it is to be understood that the con- I struction shown is merely illustrative and that such changes-may be made, when de-.

sired, as are within the scope of the appended claimi I i Having described'my invent-ion, what I claim and desire to secure by-Letters-Pat out is: e

Ihe herein described internal combustion engine,- com risinga piston .for receiving a power impu se, said piston having a central pocket in its inner end, an auxiliary piston opposed to the innerend of the power piston and havingan outwardly extending central stem of a sizeinyross-section to snugly fit inlsaid pocket and also; having an in wardly extending central plunger, and a cylinder in which said pistons are movable rectilinearly; said cylinder having an exhaust port arranged to be uncovered by the power piston at the completion of the out- .ward stroke thereof and also having a port for leading explosive mixture into the chamber' between the auxiliary piston and the cylinder head, and a passage for leading explosive mixture from said chamber to the chamber between the pistons, and further having on the cylinder head a tubular neck that receives the plunger on the auxiliary piston and terminates in a closed chamber and is provided at a point adjacent the cylinder head with a port.

In testimony whereof I have hereunto set my hand in presence of two subscribing witnesses. p

' CLARENCE o. LONGARD.

' Witnesses:

EDNA JAMES SHEEHY,

PnrLIr E. BARNES. I 

